package str

func toLowerCase(s string) string {
	bs := []byte(s)
	for i, _ := range s {
		if isUpperAlpha(s[i]) {
			bs[i] = bs[i] + 32
		}
	}
	return string(bs)
}

func isUpperAlpha(b byte) bool {
	if b >= 65 && b <= 90 {
		return true
	}
	return false
}
